Electrical connector



June 30, 1959 Filed Oct. 19, 1953 E. F. WERNDL ELECTRICAL CONNECTOR 4 Sheets-Sheet 1 59 144 Z We'V/VZQ Z iibrkvcea June 30, 1959 E. F. WERNDL ELECTRICAL CONNECTOR 4' SheetsSheet 2 gw U \w ww \\\\\\\\\\\\\\\\v Filed Oct. 19, 1955 June 3-0, 1959 a F. WERNDL ELECTRICAL CONNECTOR 7 Sheets-s 3 Filed on. 19. 1953 NJ M, A g

June 30, 1959- E. F. WERNDL 2,892,990

ELECTRICAL CONNECTOR 4 Sheets-Sheet 4 Filed Oct. 19, 1953 United States Patent ELECTRICAL CONNECTOR Ernst F. Werndl, Alamogordo, N. Mex., assignor to Land-Air, Inc., Chicago, 111., a corporation of Illinois Application October 19, 1953, Serial No. 386,902

8 Claims. (Cl. 339-60) This invention relates generally to electrical connectors, and more particularly to a novel electrical connector suitable for use under standard and ordinary conditions, as well as for use at high voltages and high altitudes which may be experienced in aircraft use.

Electrical connectors designed for high voltage application have been generally unsatisfactory for high altitude application. At high altitudes there is a greater tendency for voltage break-down of the insulating material, as well as a substantial reduction in the current carrying capacity of the connector contacts. In addition, it is important that the electrical connector be sub jected to extreme vibration without electrical break-down or deterioration of the components of the connector.

In order to overcome these objections, it is desirous that the connector be vapor-proof, and concurrently that the pressure be applied to the contacts over wide temperature ranges as well as variation in atmospheric pressure. Furthermore, ordinary connectors generally have exposed lead in wires which are a source of leakage and voltage break-down, which may constitute a serious menace to the operation of the equipment.

The principal object of the present invention is to provide a novel electrical connector which is adaptable for use not only in ordinary temperatures, but also at high altitudes, and will still handle high voltages without the danger of arcing or voltage discharge.

Another object of the present invention is to provide a novel electrical connector which is capable of being readily engaged or disengaged; and furthermore, the connector be constructed so as to assemble the lead in wires to the contacts of the male and female portions of the connector.

Another object of the present invention is to provide an electrical connector which exhibits a hermetic seal and which will operate under extreme moisture conditions, as well as varying pressures encountered at high altitudes by aircraft.

Another object of the present invention is to provide an electrical connector which will operate under impact or extreme vibration, as well as low temperatures, and should not be subject to deterioration under these conditions.

Still another object of the present invention is to provide an electrical connector wherein all the high voltage contacts and conductors are completely insulated, the connector being adapted to establish a plurality of circuit connections simultaneously by simple manual engagement, and conversely, designed for quick disconnect.

Still another object of the invention is to provide an electrical connector which provides a minimum size and weight construction, and which can be constructed according to mass production procedures.

Other objects and advantages will become apparent as the description proceeds.

Referring to the drawings:

Figure l is a side elevation view illustrating the complementary assembly of the electrical connector embodying this invention;

Figure 2 is a top plan view of the electrical connector showing the severed lead in wires;

Figure 3 is a side elevational view partly in crosssection of the disengaged electrical connector assembly;

Figure 4 is an end view in perspective on line 4-4 of Figure 3 of the male member of the electrical connector;

Figure 5 is a top end view of the female member of the electrical connector;

Figure 6 is a fragmentary view, partly in section, on line 66 of Figure 3;

Figure 7 is an enlarged fragmentary view partly in section showing the normal position of the camming spring feature;

Figure 8 is an enlarged fragmentary view partly in section showing the expanded position of the camming spring feature;

Figure 9 is a side elevation view partly in section illustrating a modified embodiment of a disengaged electrical connector assembly;

Figure 10 is a top plan of the assembly of the modified form of an electrical connector.

Figure 11 is a longitudinal cross section view of the assembled modified form of the electrical connector; and

Figure 12 is a side elevational view of a contact used in the modified form of the electrical connector.

Similar characters of reference are used in all the figures of the application to indicate corresponding parts.

Referring now to the drawings, in Figure 1 there is illustrated an electrical connector in a completely engaged relationship with respect to the male member 4 and a female member 6. The male member 4 constitutes a plug or insertable element having various geometric 'configurations, such as a frusto-conical shape, as shown, or cylindrical, trapezoidal, polyhedric, spheroid, square or rectangular configurations. The embodiment although not limited as shown in Figures 1 through 5 is substantially a frusto-conical configuration having a side arm element 12 extending from the upper portion of the male member 4.

In this embodiment the male member 4 is made of a material having a resilient composition wherein the elastomer shall be of compressible material capable of being deformed; such material may be of the various rubberlike compositions, synthetic or natural, including the silicone types as well as various plastic materials, such as polytetrafluoroethylene, monochlorotrifluorethylene, or any resilient composition or combinations thereof that have the characteristic of being compressible. Various compositions may be used in the construction of the male member; although it is highly desirable that the material exhibit acceptable electrical characteristics for insulation purposes.

The male member 4 may be molded or cast into the desired configuration. It shall be noted that the side walls 13 of the male member 4 shall generally exhibit a gradual taper in order that it may be insertable into the complementary recess 52 of the female member 6.

The complementary recess 52 of the female member 6 shall exhibit a corresponding receiving geometric configuration as the insertable male member 4. The space tolerance between the side wall 13 of the male member 4 and the side wall surface 57 of the recess 52 shall be of suflicient distance in order to allow insertion of the .male member 4. Upon compression of the male member 4, the side wall 13 of the male member 4 shall be in compressive contact with a portion of the side wall 57 of the recess 52 in the female member 6. Correspondingly, this will perform a mechanical interlock between the male member 4 and the female member 6. The degree of taper of the respective side walls 13 and 57 may vary depending upon the compressibility of the material and the composition of each of the respective side walls 13 and 57.

Various possible directions of application of pressure to the male member 4 may be performed by applying the pressure internally omnidirectional, internally tangential, internally radial and internally axial. Various sources of energy for applying the pressure may be used such as manual, hydraulic or pneumatic circuits, electric or electromechanical. Although the application of manual energy is a design requirement, the use of hydraulic or pneumatic sources are feasible.

Since a multiplication of effort is necessary, a manual device might employ a screw, gear, cam or lever system in order to compress the male member 4. The use of the screw means, as shown in Figures 9 through 12, is mechanically simple but has certain inherent disadvantages which are directed primarily to a slower time for disconnection of the members 4 and 6 as compared to a cam action design.

1\ specific embodiment as illustrated in Figures 1 through 8, utilizes a pressure device of the cam type. The cam mechanical means may be located centrally in the axis of the plug member 4. The cam surface 26 of the resilient material of the plug member 4 is shaped like a double pitch round thread formed corresponding to the cam tube 24. The cam surface 26 normally is substantially contiguous to the outside surface of the cam tube 24; although practically there is an expanding inner recess 27 in between the outside surface 25 and the cam surface 26.

The mechanical camming means may comprise a handle 14 attached to a shaft 18 by rivets 1.6 in a conventional manner. The shaft 18 extends axially through the plug member 4 having a retaining collar 20 pinned through the cam tube 24 by a rivet 22. A hearing 23 supports the cam tube 24 for rotational purposes. The rotation of the shaft 18 is restricted and locked by a ball bearing detent illustrated in Figures 3 and 6, comprising bearings 28 confined by the resilient material through openings 29 in the tube 24 and in order to ride over the form thread of the tube 24 to another position upon rotation of the shaft 18, the ball bearings 28 must be forced outwardly by the movement of the resilient material of the male member 4. A spring retainer 30 is placed over the ball bearings 28 to simplify the amount of force required and to confine the resilient material.

Figure 3 illustrates a pinned shaft 18 arrangement; although the shaft may be keyed in a conventional manner to the tube 24 in order to provide the necessary rotational camming force to the resilient material. Upon the exertion of pressure through the resilient or elastomer material, which may be considered to be analogous with the distribution of pressure in a hydraulic system, the contact pressure is proportional to the parallel projection of the area of any side wall or imbedded contact surface.

The plug member 4 has a plurality of contacts 38 positioned circumferentially in various elevations along the side wall 13 of the male member 4. These contacts 38 must be designed with suflicient effective area of its imbedded surfaces to provide the necessary contact pres sure for the given resilient pressure performed by the resilient or elastomer material. In the event of an appreciable degradation of the pressure from one contact 38 to another, which may be corrected by other construction, the effective contact area can be increased for contacts 38 at low pressure points.

In order that the applied pressure of the resilient or elastomer material. on the contact 38 be fully effective, the contact 38 and its corresponding conductors 39 and the lead. in wires 40 should float in the resilient or elastorner material. They should not be stitfiy attached to any rigid support in or adjacent to the resilient or elastomer material. Furthermore, the contact material for contacts 38 should be relatively thin in a dimension normal to the contact surface so that the contact surface itself would be flexible and would make a better surface contact.

The female receptacle or member 6 illustrated in Figures 1 through 3 and 5 illustrates a specific embodiment comprising an outer shell 50, which is of substantially rigid constmction produced from a metallic material, such as aluminum or brass, a fiber or molded resinous product, or a hard rubber. The shell 50 has an extended collar ring 66 for mounting purposes, and a threaded portion 67 for attachment to a panel. Mounting holes 53 are positioned in the upper portion of the shell 50 for mounting attachment.

In a specific embodiment, the insulating elastomer material 56 of the female member 6 may correspond in composition to that of the elastomer or resilient material of the male member 4; although the elastomer 56 of the female portion 6 may exhibit properties of a higher durometer specification. The entire female structure, fundamentally, may be formed of substantially nondeformable material. The outer shell 50 is designed to confine the elastomer 56, if used, to a substantial degree when force is applied to the male member 4 upon insertion into the complementary recess 52 of the female member 6. It shall be noted that the geometric configuration of the recess 52 shall be substantially similar to that of the geometric configuration of the male member 4. This construction is provided in order to complement the mechanical interlock between the male member 4 and the female member 6. Contacts 59 are imbedded into the insulating material 56 corresponding to a relative position as contacts 38 in the elastomer of the male member 4 in order to make electrical contact upon manual engagement of the components.

The alignment of the contacts 59 of the female memher 6 with respect to the contacts 38 of the male member 4 should correspond in order that upon application of pressure to the male member 4, electrical pressure contact may be achieved' Furthermore, the side wall 13 of the male member 4 should frictionally bear upon the side wall 57 of the recess 52 of the female member 6 in order that a mechanical interlock may be achieved. It is preferred that the contact between the side wall 13 of the male member 4 and the side wall 57 of the female member 6 be circumferentially continuous frictionally in order that a hermetic seal, similar to an O-ring, be achieved. This will prevent the accumulation of moisture or condensation within the contacts 38 and 59, thus preventing arcing or an electrical discharge. This condition is not necessary to achieve a mechanical interlock; and, therefore, it is only important that a portion of the side wall 13 be in direct contact with the side wall 57 of the female member 6 to achieve the frictional contact.

The contacts 59 in the female member 6 are fixed to conductors 60, which are imbedded in the insulating material 56 and connected to solder lugs 62 which are affixed to the lower portion of the receptacle 50 in a conventional manner as shown. A guide pin 68 extends into the recess 52 in order to accommodate the cam tube 24. The guide pin 68 has an extended flange portion 69 imbedded in the insulating material 56 for retention as well as alignment.

Figures 1, 2 and 5 illustrate recesses 54 in the female member 6 which accommodate the guide keys 42 of the male member 4 in order to define polarity of the electrical connector.

In describing the operation of the camming action, Figures 7 and 8 are illustrative of the system. In the particular drawings, the cam surface 26 of the resilient or elastomer material is strengthened by molding into the elastomer material a plurality of helical springs 36 wound to match the corresponding threaded portion of the cam tube 24. When the shaft 18 is rotated either clockwise or counter-clockwise a quarter turn to the closed position, there cannot be a screw action, for the actual position of the cam tube 24 and the elastomer material is fixed at both ends; one end by the collar 20 pressing upon the bearing 23 and at the lower end of the male member 4 by the spring washer 34 affixed to the cam tube24 by the folded portion 32. As a result, there is a cam action on the elastomer material with the elastomer material being expanded radially for substantially the full length of its contact with the cam tube 24. When the radial expansion is restricted by the recess 52, the necessary contact pressure is applied to the side walls 13 and 57 respectively, as well as to the electrical contacts 38 and 59. The use of a spring washer 34 at the lower end of the cam tube 24 is to provide some opportunity for axial movement of the tube, if the elastomer pressure is suificient to prevent the shaft 18 from being rotated a full 90 degrees in clockwise direction to a locked position. In case of counter-clockwise rotated shaft 18 the elasticity of the uppermost portion of the elastomer material, from collar 23 downwards, will take over this function.

Figures 7 and 8 illustrate the camming action wherein the tangential area 37 of the spring 36 is in contact with the outer thread 25 of the cam tube 24, thereby forcing the elastomer material in a radial direction. The normal position is shown in Figure 7 while the extended position is shown in Figure 8.

The method of connecting the lead in wires 40 to the corresponding conductors 39 of the contacts 38 in the male member is not specifically set forth; although any conventional method of integral molding of the cable and the lead in wires 40 by soldering, use of screw lugs, or welding, may be used. For purposes of illustration, in Figures 1, 2 and 3 there is shown the continuous insulation identified by the side arm 12 using an external elastomer sheath over the lead-in wires 40, thereby illustrating an integral construction which would be substan tially waterproof.

Another embodiment of this invention is shown in Figures 9 through 12. Figure 9 illustrates a simplified arrangement wherein a frusto-conical geometric configuration of the male member is illustrated by a plug or male member 72 made of a resilient or elastomer composition. The operation of the device is initially shown in the camming action device. This specific embodiment utilizes a screw action in order to apply the compressive force to the elastomer plug or male member 72. Retainer collars 74 on the lower portion and 76 on the upper portion are made of rigid material, so that the elastomer. plug 72 is retained longitudinally and will expand in a radial direction on being compressed. A screw member 80 having a head 78 is rigidly affixed to the collar 74 and inserted centrally through said plug 72. A collar 84-is inserted over said screw member 80 and a wing nut 82 having a threaded body portion 83 is inserted thereon.

Contacts are imbedded in the plug member 72 in a manner illustrated generally in Figure 11. There are various types of contacts 86, one represented by numeral 88 as shown in Figure 12. This is a formed type of contact having a soldering eyelet 90 inserted therein. Another embodiment of the contact 86 is shown in the drawing wherein a formed conductor lug 92 is affixed to a similar contact 86 having a slotted portion 94 for soldermg.

Correspondingly, a female receptacle 100 is shown wherein the receptacle portion is constructed of a substantially rigid insulating material, such as hard rubber, plastic, ceramic and the like, having a recess 102 formed therein corresponding to the geometric configuration of the plug 4. Contacts 108 are inserted in the rigid material having a threaded conductor portion 110 aflixed to the contacts 108, and a nut 112 is threaded on the conductor portion 110 in a conventional manner.

In the operation of the mechanical screw means for applying pressure to the female receptacle or member 100, the plug member 72 is inserted in the recess 102 and screw pressure is applied. The elastomer plug 72 expands radially wherein the side walls 73 apply pressure to the side walls 104 of the recess. In addition, contact pressure is applied to the contacts 86 and 108 respectively. The operation of this device is similar to that described in the aforementioned unit wherein a camming action applies the actual pressure.

The invention shall not be limited to the application of an axial or radial pressure, but that the pressure may be applied to the male member in any of the following directions, either internal omnidirectional, or internal tangential, or internal radial or internal axial.

Conversely, another embodiment utilizes the effect of an external axial or radial'pressure applied to the female receptacle. This device utilizes a resilient or elastomer material in place of the rigid material identified by numeral in Figure 9; or, if the retainer housing 50 is removed from the device as shown in Figure 3, then the elastomer material comprising the body of the female receptacle is resilient. The plug member 72 material formerly being of resilient composition is now of a rigid construction and the pressure is now applied to the female receptacle which is compressed inwardly and bears upon the rigid construction of the male member 72. This pressure may be applied by imposing a collar around the female member 100 and compressing the now elastic composition of the female member 100.

Another method for compressing the female member is as follows: The female member 100 of an elastic composition is considered as a hydraulic or pneumatic cylinder. The elastic material is molded with an internal void or voids which are filled with oil (or air) and connected to an external hydraulic (or pneumatic) circuit which provides and controls the pressure to force the elastic material in contact with the plug member by exerting pressure inwardly. Various other types of systems, such as electrical or electro-mechanical, may be used in order to compress the female member 6.

p In the design of the unit the elastomer or resilient material should exhibit temperature stability of electrical and mechanical properties over a wide temperature range from 70 to 300 F.

The material should resist compression, wetting, deformation, as well as oxidation, and in addition, it should exhibit insulation properties as well as resistance to mechanical and electrical fatigue. Furthermore, the material should exhibit good di-electric qualities as well as low moisture adsorption.

The electrical connector as described performs a hermetic seal very similar to the O-ring type. Under ordinary conditions the hermetic seal is not necessary, but there should be. sufiicient'contact pressure between the male member 72 and the female member 100 for a mechanical interlock. The configuration of the male member may also exhibit a step-wise taper which would complement the recess of the female member. Various interlocking geometric configurations may be used, and the invention is not intended to be limited to any specific configuration.

The invention also describes the application of contact pressure onto the respective contacts of the male member and female member. This is substantially a sliding pressure contact which exhibits ideal electrical conduction and high current capacity.

As many changes could be made in the above construction, and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. In an electrical connector, an elongated male member and a female member having an elongated socket therein for receiving said male member, said members having geometrically complementary surface configurations for accommodating coupling of said members in complementary fashion, said members each carrying a plurality of spaced contacts thereon in the complementary surfaces thereof and adapted to engage at least two contacts on the complementary member, said members each providing complementary sealing surfaces surrounding said contacts thereon and adapted to mate to effect a hermetic seal therebetween to seal off pairs of engaging contacts from other pairs of engaging contacts, the male one of said members being subject to radially outward deformation, and deforming means operatively associated with only said one deformable member to selectively deform said one member to cause contacts thereon to engage under pressure cooperating contacts of said complementary member while simultaneously causing said complementary sealing surfaces to mate to effect a hermetic seal therebetween which seals off pairs of engaging contacts from other pairs of engaging contacts.

2. In an electrical connector, an elongated male member and a female member having an elongated socket therein for receiving said male member, said members having geometrically complementary surface configurations for accommodating coupling of said members in complementary fashion, said members each carrying at least one contact thereon in the complementary surfaces thereof and adapted to engage a corresponding contact on the complementary member, said members each providing complementary engaging portions, other than said contacts and surrounding said contacts, which are capable, when engaged, to produce a mechanical interlock between the male and female members which keeps said members coupled together, the male one of said members being subject to radially outward deformation, and deforming means carried by only said one deformable member and including a force-applying member extending longitudinally of said deformable male member for selectively radially deforming said one memher to cause contacts thereon to engage under pressure cooperating contacts of said complementary member while simultaneously causing the complementary engaging portions to engage to effect a mechanical, frictional, interlock between the male and female members which keeps said members coupled together.

3. In an electrical connector, an elongated male member and a female member having an elongated socket therein for receiving said male member, said members having geometrically complementary surface configurations for accommodating coupling of said members in complementary fashion, said members each carrying a plurality of contacts thereon in the complementary surfaces thereof and adapted to engage corresponding confacts on the complementary member, said members each providing complementary engaging friction-generating portions on the complementary surfaces thereof, other than said contacts and surrounding said contacts, which are adapted to engage when said members are coupled together, the male one of said members being subject to radially outward deformation, and deforming means operatively associated with only said one deformable member to selectively deform said one member and to simultaneously cause contacts thereon and the engaging friction-generating portions thereof to engage under pressure cooperating contacts and engaging friction-generating portions of said complementary member, the engagement of said friction-generating portions of said members operating to maintain said members coupled together.

4. In an electrical connector having complementary male and female members, each of which has complementary contacts and insulating portions thereon which are adapted to mate, wherein the male member is of deformable material subject to expanding deformation, and wherein deforming means are operatively associated with the male member to selectively effect deforming of the male member and engaging under pressure of said complementary contacts and insulating portions of said members; the improvement in said deforming means comprising relatively flexible elongated tubular means carried by the deformable material of said male member and shaped to provide alternate ridges and valleys on the interior of said tubular means, an elongated relatively rigid actuator positioned co-axially in said tubular means and shaped to provide alternate ridges and valleys on the exterior thereof, the dimensions of said tubular means and actuator being such that when the ridges on the actuator are in register with the valleys in the tubular means then the male member is not deformed on when the ridges on the actuator and tubular means are in register then the deformable material of the male member and the tubular means carried thereby are resiliently deformed to effect an exterior deformation of the male member, and means for selectively actuating said actuator between the two conditions defined.

5. A device as set forth in claim 4 including spring means normally biasing the actuator to one of the two defined conditions.

6. A device as set forth in claim 4 wherein at least one of the actuator or tubular means is helical in form so that rotation between the two parts effects axial movement therebetween to move said parts from one of the defined conditions to the other defined condition.

7. In an electrical connector, an axially elongated male member and a female member having complementary frusto-conical surface configurations for accommodating coupling of said members in complementary fashion, said members each being of insulating material and each carrying contacts thereon in the frustoconical surface thereof and substantially flush therewith, said members each providing complementary engaging surfaces completely surrounding said contacts thereon, the male member being subject to deformation, and de' forming means operatively associated with said deformable member to deform said member to cause contacts thereon to engage under pressure cooperating contacts of said few male member while simultaneously causing said engaging surfaces thereon to engage under pressure the cooperating engaging surfaces of said female member, to thereby hermetically seal pairs of engaging contacts from other pairs of engaging contacts and to effect a frictional mechanical interlock between the male and female members which keeps said members coupled together.

8. In an electrical connector, an elongated male member having a plurality of spaced contacts positioned thereon, a female member defining a walled recess there in for receiving the male member therein and having a related number of spaced contacts in the walls of said recess for engaging the contacts on the male member, the male one of said members being of a material suit ject to deformation, portions of said two members hav ing complementary engaging surfaces, other than said contacts, which are adapted to mate, and deforming means carried only by said male member and including a force applying member extending longitudinally of said male member for selectively deforming said male member radially outwardly to cause the contacts and the engaging surfaces thereon to engage under pressure the cooperating contacts and engaging surface of said female member, and so as to effect a mechanical, frictional, hermetic interlock between the said two members which keeps the said members coupled together.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Coar Feb. 26, 1924 Peroni Mar. 14, 1933 6 Spencer Nov. 27, 1934 Winer Sept. 30, 1947 Brus Feb. 16, 1954 

